PC-UM10M
XE-A402 HARDWARE DESCRIPTION
– 8 –
Power supply/CONTROL pins
5. KEY-DISPLAY
5-1. LCD CONTROL
Basically the same as the ER-A275P.
LCD-related registers
< LCD Control Signal / Key Strobe Signal >
Bit7 : Not used
Bit6 : E
Enable Signal
Enable
Bit5 : R/W
H : Data read
L : Data Write
Bit4 : RS
H : Data input L : Instruction Input
< Data Latch Signal >
L : LCD write data latch
5-2. KEY/DISPLAY SCAN
On the A401, the key and display scan signal is common.
KEY/display SCAN and key read should be performed at the following
timing.
1
KEY/display SCAN cycle: 10ms
2
Blanking time: 50us
3
KEY DATA READ timing: More than 10 ms from the fall of the SCAN
signal
Key / Display-related registers
< LED Segment Signal >
< LCD Control Signal / Key Strobe Signal >
Bit3 ~ 0 : KS3 ~ 0
Strobe signals for keys and POP UP Display are generated at KS3 - 0.
< Key Return Signal >
PORT
PIN
No.
I/O
Pin name
Function
PORT
PIN
No.
I/O
Pin name
Function
BYTE
8
I
BYTE
Connected to VCC
Vcc
62
Vcc
Connected to VCC
CNVss
9
I
CNVss
Connected to GND
Vss
64
Vss
connected to GND
/RESET
12
I
/RESET
AVss
96
AVss
Connected to GND
Xout
13
O
Xout
OPEN
Vref
98
Vref
Connected to VCC
Vss
14
Vss
Connected to GND
AVcc
99
AVcc
Connected to VCC
Xin
15
I
Xin
connected to Spectram diffusion IC
Vcc
16
Vcc
Connected to VCC
Function
Address
R/W
LCD Write Data
04001h
W
LCD Read Data
04002h
R
LCD Control Signal / Key Strobe Signal
04003h
W
Data Latch Signal
CPU port P94
W
Address
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
04003h
–
E
R/W
RS
KS3
KS2
KS1
KS0
Function
Address
R/W
LED Segment Signal
04000h
W
LCD Control Signal / Key Strobe Signal
04003h
W
Key Return Signal
04003h
R
Address
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
04000h
dp
g
f
e
d
c
b
a
Address
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
04003h
-
E
R/W
RS
KS3
KS2
KS1
KS0
Address
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
04003h
KR7
KR6
KR5
KR4
KR3
KR2
KR1
KR0